include/crypto/internal/blake2b.h

   1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
   2 /*
   3  * Helper functions for BLAKE2b implementations.
   4  * Keep this in sync with the corresponding BLAKE2s header.
   5  */
   6
   7 #ifndef _CRYPTO_INTERNAL_BLAKE2B_H
   8 #define _CRYPTO_INTERNAL_BLAKE2B_H
   9
  10 #include <crypto/blake2b.h>
  11 #include <crypto/internal/hash.h>
  12 #include <linux/string.h>
  13
  14 void blake2b_compress_generic(struct blake2b_state *state,
  15                               const u8 *block, size_t nblocks, u32 inc);
  16
  17 static inline void blake2b_set_lastblock(struct blake2b_state *state)
  18 {
  19         state->f[0] = -1;
  20 }
  21
  22 typedef void (*blake2b_compress_t)(struct blake2b_state *state,
  23                                    const u8 *block, size_t nblocks, u32 inc);
  24
  25 static inline void __blake2b_update(struct blake2b_state *state,
  26                                     const u8 *in, size_t inlen,
  27                                     blake2b_compress_t compress)
  28 {
  29         const size_t fill = BLAKE2B_BLOCK_SIZE - state->buflen;
  30
  31         if (unlikely(!inlen))
  32                 return;
  33         if (inlen > fill) {
  34                 memcpy(state->buf + state->buflen, in, fill);
  35                 (*compress)(state, state->buf, 1, BLAKE2B_BLOCK_SIZE);
  36                 state->buflen = 0;
  37                 in += fill;
  38                 inlen -= fill;
  39         }
  40         if (inlen > BLAKE2B_BLOCK_SIZE) {
  41                 const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2B_BLOCK_SIZE);
  42                 /* Hash one less (full) block than strictly possible */
  43                 (*compress)(state, in, nblocks - 1, BLAKE2B_BLOCK_SIZE);
  44                 in += BLAKE2B_BLOCK_SIZE * (nblocks - 1);
  45                 inlen -= BLAKE2B_BLOCK_SIZE * (nblocks - 1);
  46         }
  47         memcpy(state->buf + state->buflen, in, inlen);
  48         state->buflen += inlen;
  49 }
  50
  51 static inline void __blake2b_final(struct blake2b_state *state, u8 *out,
  52                                    blake2b_compress_t compress)
  53 {
  54         int i;
  55
  56         blake2b_set_lastblock(state);
  57         memset(state->buf + state->buflen, 0,
  58                BLAKE2B_BLOCK_SIZE - state->buflen); /* Padding */
  59         (*compress)(state, state->buf, 1, state->buflen);
  60         for (i = 0; i < ARRAY_SIZE(state->h); i++)
  61                 __cpu_to_le64s(&state->h[i]);
  62         memcpy(out, state->h, state->outlen);
  63 }
  64
  65 /* Helper functions for shash implementations of BLAKE2b */
  66
  67 struct blake2b_tfm_ctx {
  68         u8 key[BLAKE2B_KEY_SIZE];
  69         unsigned int keylen;
  70 };
  71
  72 static inline int crypto_blake2b_setkey(struct crypto_shash *tfm,
  73                                         const u8 *key, unsigned int keylen)
  74 {
  75         struct blake2b_tfm_ctx *tctx = crypto_shash_ctx(tfm);
  76
  77         if (keylen == 0 || keylen > BLAKE2B_KEY_SIZE)
  78                 return -EINVAL;
  79
  80         memcpy(tctx->key, key, keylen);
  81         tctx->keylen = keylen;
  82
  83         return 0;
  84 }
  85
  86 static inline int crypto_blake2b_init(struct shash_desc *desc)
  87 {
  88         const struct blake2b_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
  89         struct blake2b_state *state = shash_desc_ctx(desc);
  90         unsigned int outlen = crypto_shash_digestsize(desc->tfm);
  91
  92         __blake2b_init(state, outlen, tctx->key, tctx->keylen);
  93         return 0;
  94 }
  95
  96 static inline int crypto_blake2b_update(struct shash_desc *desc,
  97                                         const u8 *in, unsigned int inlen,
  98                                         blake2b_compress_t compress)
  99 {
 100         struct blake2b_state *state = shash_desc_ctx(desc);
 101
 102         __blake2b_update(state, in, inlen, compress);
 103         return 0;
 104 }
 105
 106 static inline int crypto_blake2b_final(struct shash_desc *desc, u8 *out,
 107                                        blake2b_compress_t compress)
 108 {
 109         struct blake2b_state *state = shash_desc_ctx(desc);
 110
 111         __blake2b_final(state, out, compress);
 112         return 0;
 113 }
 114
 115 #endif /* _CRYPTO_INTERNAL_BLAKE2B_H */